Plier with locking feature on pawl



Dec. 19, 1961 A. E. ERICSON 3,013,456

PLIER WITH LOCKINGFEATURE ON PAWL Filed Sept. 29. 1959 INVENTOR. ALF ERNFERD ERICSON BY =WMM ATTORNEYS.

United States Patent 3,013,456 Patented Dec. 19, 19.61

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This invention relates to a plier assembly having a locking feature which enables the assembly to function either as a plier assembly or as a wrench.

However, in all these prior cases, it has been found that one tool function is necessarily emphasized to the detriment of the other tool functions thereby decreasing the efficiency of the other tool functions.

It is an object of the present invention to provide a tool which can function equally well as either pliers or wrench without imparing the efficiency of either operation.

More particularly the present invention has as its obplier assembly having a locking feature thereon which when disengaged enables the assembly to function as a pair of pliers.

A further object of the present invention is to provide a plier assembly having a locking feature thereon which when engaged enables the assembly to function as an adjustable wrench.

of pliers or as an adjustable wrench.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same the accompanying drawings wherein:

FIG. 1 is a front elevational view of an embodiment of the present invention wherein the jaws of the plier assembly are closed and the locking feature engaged in a last notch;

FIG. 2 is a fragmentary side elevational view of the pliers of FIG. 1;

FIG. 3 is a fragmentary front elevational view of the pliers of FIG. 1 but showing the plier assembly in open position and the locking feature disengaged;

FIG. 4 is a fragmentary front elevational view of the FIG. 5 is an enlarged fragmentary view of FIG. 4 showing the pawl tooth engaged in a first notch.

Specific reference is now made to the drawings wherein like reference characters are used for like elements throughout.

56 of locking pawl 58 which is pivotally secu'red'to plier member 18 via rivet or pin 60.

Pawl 58 possesses a lever member 62 tion to shoulder 48 of plier member 1' In operation, when jaws 32 and 34 are moved from the relatively open position of FIG. 4 towards the closed position of FIG.'1 to grasp an object, the wedging action in gliding up side of pawl tooth 56 (FIG. 5) causes said pawl tooth 56 to pivot for a small angle in a clockwise direction about pin as well as urging end of spring 66 in a left hand direction. The gliding of side 53 up side 55 of pawl tooth 56 continues until the entire side 53 v including tip 51 thereof (as shown in phantom lines in FIG. 5) has passed tip 59 of pawl tooth 56. tip 59, pawl tooth 56 immediately snaps into neighboring notch 52 because end 65 of dead center spring 66 is still positioned to the as shown in FIG. 1.

However, the jaws of the tion can be opened only if from notches 50,

will not pivot in a counterclockwise direction about pin Thus retrograde movement of jaws 32 and 34 is precluded unless and until pawl tooth 56 is disengaged.

It is thus seen that when pawl tooth 56 is engaged with notches 52 or 54 a wrench adjustable towards a may be used as a pair of pliers.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed as the invention is:

1. A plier assembly with locking feature on pawl comtherein,

each include first and second sides inclined at different angles, said first side being inclined to exert a camming action against said tooth to cause said tooth to pivot for a small angle and thus engage successive notches as said jaws are closed whereas said second side of said notch is inclined to exert a bearing action against said tooth to restrain the pivoting of said tooth thereby precluding the opening of said jaws until said tooth is disengaged from said notches.

3. The plier assembly of are formed concentric with attachment.

4. In a plier assembly including pivoted handle members and jaws with opposing jaw pieces extending therefrom the improvement comprising providing a plurality of notches on said assembly, pivotally mounting on said assembly a pawl having a tooth adapted to engage one of said notches and providing a spring operatively secured to said pawl and to one of said handle members, said spring having a first stable position and a second stable claim 1 wherein said notches the point of said pivotal position such that when said spring is in the first stable position said tooth is resiliently biased into engagement with one of said notches, and when said spring is in said second stable position, said tooth is resiliently biased away from said notches, said notches being formed with sides inclined at difierent angles to permit said tooth to pivot and engage successive notches as said jaws are closed and to restrain the pivoting of said tooth to preclude the opening of said jaws until said tooth is disengaged from said notches.

5. The plier assemblying of claim 4 wherein said notches are formed on said assembly concentric with the point of said pivotal mounting. 15 References Cited in the file of this patent UNITED STATES PATENTS 1,426,553 Cruickshank Aug. 22, 1922 1,475,834 Kadow Nov. 27, 1923 20 2,577,008 Engstrom Dec. 4, 1951 

